Bottle base



FIG. 1 is a perspective view of the bottle base of the present invention;

FIG. 2 is a side view of the bottle base of FIG. 1 with portions shown in phantom;

FIG. 3 is a bottom view of the bottle base of FIG. 1; and,

FIG. 4 is a top view of the bottle base of FIG. 1.

The broken line showing in FIGS. 3 & 4 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a bottle base, as shown and described. 